1. Field of the Invention
The invention relates to a combination housing of a notebook computer, and more particularly, to a combination housing of a notebook computer having a display housing and a main frame housing each of which includes two metal covers that are attached to a middle plastic frame, thereby forming a sandwich structure.
2. Description of the Related Art
With the advancement of production technology and the rationalization of price, the notebook computer has gradually replaced the desktop computer and becomes essential merchandise in the computer market. Previously, the notebook computer met working requirements of few professionals, and now it has been made widely available to all kinds of people. Therefore, in addition to having complete functions, the notebook computer also has to own shock resistance and can be protected from the electromagnetic interference. Even, it has to fulfill the recycling requirement by recovering of old notebooks for catering to the need of the market.
As shown in FIGS. 1 and 2, a conventional notebook computer 60 includes a display 40 and a main frame 50. The bottom rim of the display 40 is pivotally coupled to the rear side of the main frame 50. The display 40 includes a display panel 42, a rear housing 41 for accepting the display panel 42, and a front housing 43 for holding the display panel 42 in place. The display panel 42 includes LCD or other self-illuminating elements and contains a corresponding positioning bar 421 and positioning pieces 422 at two sides thereof. The positioning rods 421 each have a hinge 423 at the bottom thereof for a pivotal connection to a connection bar (not shown). In this way, the display 40 and the main frame 50 can be pivotally joined together. So, the display 40 can be swiveled on the main frame 50 in an open or a closed position.
The main frame 50 consists of a top housing 51 and a bottom housing 52 both of which are joined together to form a main frame housing 50A. The top housing 51 and the bottom housing 52 define a receiving space for holding a keyboard 53, a mother board and other electronic devices (e.g. hard disk drive, optical devices, etc.) that are not shown in the figures. So, the top housing 51 and the bottom housing 52 have to be provided with corresponding grooves 511, 521 and partition ribs 522.
The housing structure of the above-mentioned notebook computer 60 primarily consists of the rear housing 41, the front housing 43, the top housing 51, and the bottom housing 52. Other small elements are not described hereinafter. These four portions are mainly formed by an injection molding process of plastic and ABS (acrylonitrile butadiene styrene) or PC (Polycarbonate)+ABS material, and then fastened with screws or engaging elements. However, these plastic housings have to undergo a special surface treatment with printing or coating process. This results in recovery difficulties later. Moreover, the whole plastic injection molding machine is expensive. Meanwhile, the plastic strength is not so high as metal strength so that the thickness of the plastic housings has to be maintained above 0.8-1.2 mm for ensuring a sufficient material strength. Otherwise, the computer housing is easily damaged. So, the cost thereof is not low as well. In addition, the use of the plastic housing can't prevent the notebook computer from electromagnetic interference. This is a big imperfection, too.
Currently, the conventional plastic housing still leaves much to be desired. The aluminum magnesium alloy is applied to the notebook computer due to its light weight, high mechanical strength, and excellent texture. Unlike the plastic goods that can be formed by injection molding process with high efficiency, the aluminum magnesium alloy goods are made only by die casting that requires a molding tool cost triple as high as the injection molding tool cost. Moreover, the yield rate is too low as well so that the production cost is considerably increased. Accordingly, this is only applicable to the products with the requirement of the top quality. So, the production is commonly done by stamping process. However, the stamping elements still have many restrictions. For example, the depth can't be too large; otherwise, the stamping process will be completed with difficulties. The connection between metal stamping elements often produces assembly problems due to precision control difficulties. Thus, the stamping element made of aluminum ally or aluminum magnesium alloy can only be applied to the rear housing 41, rather than to the front housing 43, the top housing 51 and the bottom housing 52 due to the aforementioned factors.